Offshore production installations such as those used for drilling wells, or merely for producing or processing crude oil and gas, are usually equipped to permit at least some degree of heat exchange with fluids utilized on the platform. Such equipment can be utilized in the actual production operation such as by internal combustion engines which drive the drilling apparatus. It could also include processing equipment which handles and treats produced crude oil and gas.
In either instance the normal practice is to utilize to a large extent heat exchange with the surrounding air for cooling processing fluids. However, air type heat exchangers are generally relatively large in order that the proper exchange rate can be achieved.
On any offshore drilling installation, space is at a premium. Thus, any space occupied by heat exchangers such as those which utilize the air as a heat exchange medium, tend to take up more room than is necessary.
A further disadvantage inherent in the usual air type heat exchanger, is that the temperature of the air utilized to cool the process fluid can rise to the point where relatively little temperature differential exists between the air and fluid. For example, in tropical installations, the air will often exceed 100.degree. F. To achieve any suitable degree of fluid cooling with air of this temperature, an excessive amount of heat exchange surface will be required.
Toward overcoming this problem of cooling a process fluid while utilizing as little deck space as possible, there is presently disclosed means on an offshore platform for efficiently and effectively cooling process fluids. Such means in one embodiment includes a closed circuit which carries an intermediary fluid, preferably a liquid such as water. The latter is circulated into heat exchange contact with both the process fluid, and with the surrounding sea water. Thus, by regulating the volumetric flow of intermediary liquid, it is possible to minimize the amount of on-deck or exposed heat exchange equipment, while achieving the maximum effect of the heat sink capabilities of the surrounding body of water.
It is therefore an object of the invention to provide a heat exchange system for an offshore installation which includes utilization of the surrounding water as a heat sink or heat exchange medium. A further object is to provide a heat exchange system of the type contemplated in which an exemplary degree of temperature control can be effectuated by regulating the amount of heat which is transferred to surrounding waters. A still further object is to provide a relatively simple heat exchange system in which submerged portions of an offshore platform are utilized to avoid the unnecessary utilization of deck space on the platform.